Currently Google's mapped actual trees in 3D—80 million of them according to TechCrunch—in cities across the globe, including San Francisco, Tokyo, Athens, and Chicago. To enable trees, you'll need to tick the Trees checkbox inside the 3D Buildings layer.

Watch the video above for a look at the new feature in action. In addition to Trees, Google Earth 6 has added much improved Street View support. You can either zoom until Street View is automatically enabled, or you can drag the familiar yellow Street View avatar (called "peg man") to the street you want to see. You can also switch between Street View or 3D ground level mode (the latter shows the 3D buildings and trees).